Leg holder system for simultaneous positioning in the abduction and lithotomy dimensions

ABSTRACT

A leg holder system for simultaneously positioning in the abduction and lithotomy dimensions including a support device for supporting a leg cradle; a clamping device for mounting the proximate end of the support device to a mounting device having a first axis and selectively clamping and releasing motion of the support device about the first axis and about a second axis transverse to the first axis. An actuator device for actuating the clamp to selectively clamp and release simultaneously the support device and the mounting device; and an operator device remote from the clamping device and actuator device for operating the actuator device to enable the support device to move simultaneously about the first and second axis in both the lithotomy and abduction dimensions.

This application is a Reissue of U.S. patent application Ser. No.08/813,708, filed on Mar. 7, 1997 and now U.S. Pat. No. 5,802,641.

FIELD OF INVENTION

This invention relates to an improved leg holder system and moreparticularly to such a system in which adjustment in both the lithotomyand abduction dimensions can be made simultaneously with a singleaction.

BACKGROUND OF INVENTION

In recent years many newer surgical procedures have requiredinteroperative positioning of patients legs. Until recently suchpositioning typically required adjusting the leg holder's mounting clamplocated on the surgical table siderail, beneath the sterile drape. Thisraised concerns about possible violation of the sterile field and itlimited the performance of such adjustments to non-sterile personnel.Recent attempts to solve this problem yielded leg holders that could beraised and lowered through the drapes, however, they have severallimitations. First, when adjusted upwardly they lock by means of aratchet mechanism; this mechanism does not prevent further unintendedupward movement of the legs that could result from tilting the patientin the extreme head down direction “Trendelenburg” or from surgicalstaff leaning against the leg holder. Secondly, abduction ispredetermined and cannot be adjusted without accessing the mountingclamp.

SUMMARY OF INVENTION

It is therefore an object of this invention to provide an improved legholder system.

It is a further object of this invention to provide such a system withwhich both the lithotomy and abductions for a leg holder can be adjustedwith a single action with one hand.

It is a further object of this invention to provide such a system whichpermits adjustment without violating the sterile field.

It is a further object of this invention to provide such a system whichprevents further inadvertent upward movement even when the patient istilted in the extreme head down or Trendelenburg direction.

It is a further object of this invention to provide such a system whichwhen locked prevents movement in all directions.

It is a further object of this invention to provide such a system whichpermits a full abduction adjustment range throughout the full lithotomyrange.

It is a further object of this invention to provide such a system whichthe clamps are normally locked and must be activated for release.

It is a further object of this invention to provide such a system whichrelease of the actuation of the clamps causes them to default to thelocked condition.

It is a further object of this invention to provide such a system inwhich the clamps are remotely operable.

It is a further object of this invention to provide such a system inwhich the clamping operation is accomplished through the sameinstrumentality as the re-positioning of the leg holders.

It is a further object of this invention to provide such a system inwhich the leg holders are counterbalanced for reducing the loadencountered by the user with a patient in place.

It is a further object of this invention to provide such a system inwhich the operation of the clamping means can be accomplished with thesame action as the repositioning of the leg holders or can be decoupledfor independent operation.

This invention results from the realization that a truly simple,fail-safe leg holder system which enables simultaneous positioning inthe abduction and lithotomy dimensions with a single action outside thesterile field can be effected using an actuator that is normally biasedto clamp both the leg cradle support device and a mounting device whichhave a mutually transverse axes and under control of a remote operatorsimultaneously releases the clamping force in both devices to enablemovement of the support device about both axes for repositioning in boththe abduction and lithotomy dimensions.

This invention features a leg holder system for simultaneous positioningin the abduction and lithotomy dimensions. There is a support device forsupporting a leg cradle and a clamping device for mounting the proximateend of the support device to a mounting device having a first axis andselectively clamping and releasing motion of the support device aboutthe first axis and about a second axis transverse to the first axis. Anactuator device actuates the clamp to selectively clamp and releasesimultaneously the support device and the mounting device. An operatordevice remote from the clamping device and actuator device operates theactuator device to enable the support device to move simultaneouslyabout both the first and second axes in the abduction and lithotomydimensions.

In a preferred embodiment the clamping device may include a pair ofpressure blocks a first recess for receiving the mounting device and asecond recess for receiving a support device. The clamping device mayinclude a device for biasing the blocks to normally produce frictionbetween the recesses and their respective mounting and support devicesto clamp them in position. The actuator device may include an actuatorrod extending with a support device. The support device may include abore and the actuator rod may be disposed in the bore. The actuatordevice may include a camming device fixed to the actuator rod and afollower device disposed in the clamping device and responsive to thecamming device for opposing the biasing device to simultaneouslydecrease the friction force on the support device and on the mountingdevice to release the clamping device in both axes. The operator devicemay include a handle for both operating the actuator device to remotelyrelease and secure the clamping device to the support device and themounting device and to position the support device in the abduction andlithotomy dimensions. The support device may include a resilient devicefor counterbalancing the weight of the leg holder. The axis of thehandle may be coincident with the axis with the actuator rod forindependent actuation of the clamping device and motion of the supportdevice in the lithotomy and abduction dimensions. The handle may includea rotatable sleeve. The support device may include a leg cradle bracketfor mounting a leg cradle spaced from the axis of the support means. Theactuator device may include a limiter device for arresting movement ofthe camming device before its highest position to enable the biasingdevice to back-drive the camming device when the operator device isreleased and automatically reestablish the clamping function between therecesses and the support and mounting devices.

DISCLOSURE OF PREFERRED EMBODIMENT

Other objects, features and advantages will occur to those skilled inthe art from the following description of a preferred embodiment and theaccompanying drawings, in which:

FIG. 1 is a detailed sectional view of a leg holder system with portionsbroken away and foreshortened of a leg holder system according to thisinvention;

FIG. 2 is a view similar to FIG. 1, with the support device rotated 90°;

FIG. 3 is an exploded view of the leg holder system shown in FIGS. 1 and2;

FIG. 4 is a pair of leg holder systems according to this invention asshown in FIGS. 1, 2 and 3 installed on an x-ray table with leg cradlesand leg cradle clamps installed and employing gas cylinder liftassistance devices;

FIG. 5 is a view similar to FIG. 4 with the leg cradles repositionedwith greater abduction and lesser lithotomy; and

FIG. 6 is a view similar to FIG. 4 with the leg cradles repositionedwith greater lithotomy and lesser abduction.

There is shown in FIG. 1, leg holder system 10 according to thisinvention which enables simultaneous positioning in the abduction andlithotomy dimensions. Leg holder system 10 includes support device 12for supporting a leg cradle not shown in FIG. 1, but seen in FIGS. 4, 5,and 6. System 10 also includes a clamping device 14, actuator device 16,and an operator device, handle 18. Support device 12 includes a hollowtube 20 which has its proximal end 22 located in clamping device 14 andits distal end 24 at handle 18. Limiter device 26 shown more completelyin FIG. 3, is mounted at the distal end 24 of hollow tube 20. Clampingdevice 14 includes a clamp housing 30 having a recess 32 which receivesand clamps a mounting device such as pivot post 34 extending from anx-ray table. Clamp housing 30 is rotatable about axis 36 of pivot post34 which allows motion in the abduction dimension indicated by arrow 35.

Clamp housing 30 also includes a bore 38 which receives pressure blocks40 and 42. Pressure block 40 has a bore 44 through it which receives thebody 46 of pressure block 42. The enlarged tapered head 48 of pressureblock 40 fits in the enlarged tapered bore 50 of clamp housing 30.Enlarged tapered head 52 of pressure block 42 fits in an enlargedtapered bore 54 of clamp housing 30. The distal end 56 of pressure block42 includes threads 58 which mate with threads 60 on locking nut 62. Theenlarged head 64 of locking nut 62 engages one of two oppositely facingBelleville washers 66 and 68 located in recess 69. Thus, when lockingnut 62 is tightened down on pressure block 42 it compresses theBelleville washers 66 and 68. This causes the tapered portions 48 and 52of pressure blocks 40 and 42 the force of the Belleville washers to bedrawn tightly inwardly against the tapered recesses 50 and 54 of clamphousing 30. This wedging effect insures a good tight clamping forcewhich brings clamp housing together by narrowing gap 70 and therebytightening recess 32 about pivot post 34 and simultaneously wedgingpressure blocks 42 and 40 tightly in the tapered recesses 50 and 54,respectively, so that they are held against rotation in the lithotomydimension about their central axis 72 as shown by arrow 74.

Thus, in the normal condition locking nut 62 is tightened downsufficiently to compress Belleville washers 66 and 68 so that a clampingforce is applied to prevent rotation 74 about axis 72 in the lithotomydimension and prevent rotation 35 about axis 36 in the abductiondimension. Release of both of these clamping forces in both dimensionsis accomplished simultaneously by rotating handle 18 about axis 80 asindicated by arrow 82. This rotation causes actuator rod 84 to rotatealong with actuator member 86 which is fixed by pin 88 to rotate withrod 84. Pressure block 42 includes a bore 75 which is larger than butcoaxially aligned with a similar bore 76 in pressure block 40. Theproximal end 22 of tube 20 of support device 12 passes through bores 75and 76 and is fixed or force fitted to bore 76 so that when handle 18and tube 20 of support device 12 are rotated up out of the paper asindicated by arrow 77 the entire pressure block assembly includingpressure blocks 40 and 42 is rotated with tube 20.

Actuator member 16 includes two bearing portions 90 and 92 which receiveneedle bearings 94 and 96 that enable rod 84 to rotate smoothly withintube 20. Bearing 96 is supported in journal 98 fitted in the end of tube20. Between bearing portions 90 and 92 is eccentric portion 100 whichalso supports a needle bearing 102. Riding on needle bearing 102 isfollower 104 which extends through bore 106 in the proximal end 22 oftubing 20. The end 108 of follower 104 is cylindrically shaped to engagethe cylindrical shape of needle bearing 102. The other end 110 isconcave or cup shaped to engage the spherical tip 112 of set screw 114which is threadibly engaged in bore 116 of pressure block 42. Thus, whenhandle 82 is rotated about axis 80 it rotates the eccentric portion 100to bear on follower 104 which in turn exerts an outward force on setscrew 116. As a result there is a force directed along axis 72 whichopposes the bias of Belleville washers 66 and 68 thereby releases theforce of pressure blocks 40 and 42 on tapered portions 50 and 54 ofclamp housing 30. This allows clamp housing 30 to spread somewhatthereby increasing the length of gap 70 so that recess 32 relaxes itsgrip on pivot post 34 and permits rotation as indicated by arrow 35 inthe abduction direction and simultaneously permits pressure blocks 40and 42 to rotate in the tapered recesses 50 and 54 so that actuator rod84 and tube 20 of support device 12 can be rotated in a direction out ofor into the paper as indicated by arrow 77.

Thus with one action, the rotation of handle 18 about axis 80, the clampreleases its grip to allow rotation about both axis 36 and axis 72 toprovide simultaneous repositioning in the abduction and lithotomydimensions. When the handle is released the force of Belleville washers66 and 68 back-rotate the eccentric, snapping the handle to the normalposition and allowing the Belleville washer to reinstate the clampingforce on both axes. Covers 120 and 122 may be installed to cover theheads of pressure blocks 40 and 42, respectively.

The rotation of support device 12 in the direction of arrow 77, FIG. 1,is shown in FIG. 2, where upon the rotation of handle 18 about axis 80and the application of eccentric 100 to counteract the clamping force ofBelleville washers 66 and 68, the entire support device 12 includingtube 20 and the actuator rod 84 have been rotated from the plane of thepaper in FIG. 1, to the upright position where tube 20 and actuator rod84 are perpendicular to the plane of the paper in FIG. 2.

The rotational symmetry as well as rotational action may be betterunderstood with reference to the exploded three dimensional view in FIG.3. Also shown in FIG. 3 is collar 130 which is held to the end of tube20 by means of set screw 132 and the limiter collar 26a on the other endof tube 20 which is held there by means of set screws 140 and 142. Acircumferential slot 144 which extends less than all the way around thecircumference of limiter collar 26a receives limiter pin 146 fixed torotate with actuator rod 84. A pair of bushings 148 and 150 are mountedon either end of limiter pin 146 after it is mounted in hole 152 ofactuator rod 84 to provide for a smoother rotation within slot 144. Itis limiter pin 146 in conjunction with the limited extent of slot 144that arrests the rotation of actuator rod 84 before it reaches top deadcenter on the cam so that upon release by the human operator of handle18 the handle and actuator rod 84 snap back to the position where theydo not oppose the force of Belleville washer 66 and 68 and so theBelleville washers reinstate the fail-safe clamping force on both axes.Handle 18 is rotatably mounted on pin 160 which is mounted for rotationabout axis 85 on pin 162. Pin 62 includes a groove 164 that allows itand handle 160 to rotate about axis 85 but which engages with springloaded balls 166 and 168 that prevent the handle 160 and pin 162 frombeing withdrawn from the hollow end 170 of actuator rod 84.

Although thus far the system can be shown as actuated by mechanicaldevice namely, the action of eccentric 100. This is not a necessarylimitation of the invention, for example, any device may be substitutedfor eccentric 100 which will exert the opposing force on follower 104 ora similar device to release the action of Belleville washers 66 and 68on the pressure blocks and clamp pressure blocks 40 and 42 and clamphousing 30. For example, a hydraulic piston could be installed in placeof eccentric 100 driven through hydraulic lines by a foot pedal, forexample, which would be remote from the device and external to thesterile drapes. Similarly an electrical device having a movable armaturecould be used in the same fashion or even a piezo electric crystal orsimilar device when only small mechanical movements are required.

Typically, in use, two such systems 10a and 10b are used in conjunctionwith an x-ray table 180, FIG. 4. X-ray table 180 includes two rails 182and 184 on which slide blocks 186 can be slid into and out of the planeof the paper and tightened at a desired location by handles 190 and 192.Pivot posts 34a and 34b extend upward from clamps 186 and 188 intorecesses 32a and 32b, not shown, of clamp housings 30a and 30b. Mountedon each support device 20a and 20b are leg cradles (leg holders) 200 and202 pivotally mounted on axes 204 and 206 which are spaced from the axes80a and 80b of tubes 20a and 20b by support shafts 208 and 210 which aresupported in clamps 212 and 214 that are clamped into position on tubes20a and 20b by handles 216 and 218. The lifting of the weight of thissystem including cradles 200 and 202 and the legs of the patient may beassisted by means of springs or gas cylinders or other devices assymbolically indicated by gas cylinders 220 and 222 mounted to supporttubes 20a and 20b by clamps 224 and 226 and mounted to pivot posts 34aand 34b by clamps 228 and 230.

In FIG. 4, cradles 200 and 202 are in a midrange position with respectto the lithotomy and abduction dimensions. By simply gripping handles18a and 18b and rotating them in the direction of arrows 230 and 232 theeccentric members are engaged opposing the Belleville washer force andfreeing up and releasing the clamping action on both axes 32a and 32band axes 72a and 72b. Now by simply moving the handles downwardly asindicated by arrows 240 and 242 the cradles 200 and 202, FIG. 5, can bemoved to a lower position in the lithotomy dimension and may be spreadfarther apart in the abduction dimension as shown in FIG. 5, oralternatively the same motion of handles 18a and 18b in FIG. 4, whichreleases the clamp in both dimensions. After the operation of both ofthem which releases them in both dimensions the handles 18a and 18b canbe moved upwardly to increase the position in the lithotomy dimensionand reduce somewhat the position in the abduction dimension as shown inFIG. 6. In each case upon the accidental or intentional release of thehandles 18a and 18b the limiter device allows the Belleville washers tosnap the handles and the actuator rods and the eccentric out of positionso that the Belleville washers, once more in a fail-safe mode, apply theclamping force in both dimensions.

Although specific features of this invention are shown in some drawingsand not others, this is for convenience only as each feature may becombined with any or all of the other features in accordance with theinvention.

Other embodiments will occur to those skilled in the art and are withinthe following claims:

1. A leg holder system for simultaneous positioning in an abductiondimension and a lithotomy dimension comprising: a support device, havinga longitudinal axis, for supporting a leg cradle; a clamping device formounting a proximate end of said support device to a mounting devicehaving a first axis transverse to said longitudinal axis and selectivelysimultaneously clamping and releasing motion of said support deviceabout said first axis and about a second axis transverse to both saidfirst axis and said longitudinal axis, said support device fixed in saidclamping device from rotation about said longitudinal axis; an actuatordevice for actuating said clamping device to simultaneously selectivelyclamp and release said support device and said mounting device; and anoperator device remote from said clamping device and said actuatordevice for operating said actuator device to enable said support deviceto move jointly about both said first and said second axes in theabduction and lithotomy dimensions.
 2. The leg holder system of claim 1in which said clamping device includes a pair of pressure blocks, afirst recess for receiving said mounting device and a second recess forreceiving said support device.
 3. The leg holder system of claim 2 inwhich said clamping device includes a biasing device for biasing saidblocks to normally produce friction between said recesses and theirrespective mounting and support devices to clamp them in position. 4.The leg holder system of claim 1 in which said actuator device includesan actuator rod extending with said support device.
 5. The leg holdersystem of claim 4 in which said support device includes a bore and saidactuator rod is disposed in said bore.
 6. The leg holder system of claim4 in which said actuator device includes a camming device fixed to saidactuator rod and a follower device disposed in said clamping device andresponsive to said camming device for opposing said biasing device tosimultaneously decrease the friction force on said support device and onsaid mounting device to release the clamping device in both axes.
 7. Theleg holder system of claim 1 in which said operator device includes ahandle for both operating said actuator device to remotely release andsecure said clamping device to said support device and said mountingdevice and to position said support device in the abduction andlithotomy dimensions.
 8. The leg holder system of claim 1 in which saidsupport device includes a resilient device for counterbalancing theweight borne by said support device.
 9. The leg holder system of claim 6in which said operator device includes a handle for both operating saidactuator device to remotely release and secure said clamping device tosaid support device and said mounting device and to position saidsupport device in the abduction and lithotomy dimensions.
 10. The legholder system of claim 9 in which the axis of said handle is coincidentwith the axis of said actuator rod for independent actuation of saidclamp device and motion of said support device in the lithotomydimension.
 11. The leg holder system of claim 7 in which said handleincludes a rotatable sleeve.
 12. The leg holder system of claim 1 inwhich said support device includes a cradle bracket for mounting a legcradle spaced from said longitudinal axis of said support means.
 13. Theleg holder system of claim 6 in which said actuator device includes alimiter device for arresting movement of said camming device before itshighest position to enable said biasing device to back-drive saidcamming device when said operator device is released and automaticallyre-establish the clamping friction between said recesses and saidsupport and mounting devices.
 14. A leg positioning apparatus comprisinga mounting device configured to be attached to a surgical table, asupport device having a longitudinal axis, the support device beinghollow, a clamping device for mounting a proximate end of the supportdevice to the mounting device having a first axis transverse to saidlongitudinal axis, the clamping device being configured to selectivelysimultaneously clamp the motion of the support device about the firstaxis and about a second axis transverse to both the first axis and thelongitudinal axis and to selectively simultaneously release the motionof the support device for movement about said first and second axes,said support device being fixed in said clamping device from rotationabout said longitudinal axis, wherein the clamping device includes aplurality of clamping elements, at least one first clamping element ofthe plurality of clamping elements is movable between a first clampingposition to prevent the motion of the support device about the firstaxis and a first releasing position to release motion of the supportdevice about the first axis, at least one second clamping element of theplurality of clamping elements being movable between a second clampingposition to prevent the motion of the support device about the secondaxis and a second releasing position to release motion of the supportdevice about the second axis, wherein the simultaneous motion of thesupport device about the first and second axes is permitted after the atleast one first clamping device element is moved to the first releasingposition and after the at least one second clamping device element ismoved to the second releasing position, wherein the simultaneous motionof the support device about the first and second axes is prevented afterthe at least one first clamping device element is moved to the firstclamping position and after the second clamping device element is movedto the second clamping position, at least one actuator device configuredto move the at least one first clamping device element and the at leastone second clamping device element to the respective first and secondreleasing positions, at least a portion of the at least one actuatordevice extending within the support device, an operator device situatedadjacent a distal end of the support device, the handle being movable toactuate the at least one actuator device to move the first and secondclamping device elements between the respective first and secondreleasing positions and the respective first and second clampingpositions, and a leg cradle supported by the support device between theoperator device and the clamping device and movable about a plurality ofleg cradle axes relative to the support device, wherein the leg cradleis movable about the first plurality of axes when the support device isclamped against movement about the first and second axes.
 15. The legpositioning apparatus of claim 14, wherein the first axis about whichthe support device rotates corresponds to an abduction dimension and thesecond axis about which the support device rotates corresponds to alithotomy dimension.
 16. The leg positioning apparatus of claim 14,wherein the support device comprises an elongated tube.
 17. The legpositioning apparatus of claim 16, wherein the operator device comprisesa handle positioned adjacent the distal end of the elongated tube. 18.The leg positioning apparatus of claim 17, wherein the longitudinal axisof the support device passes through the handle.
 19. The leg positioningapparatus of claim 16, wherein the portion of the actuator extendingwithin the support device comprises a rod extending with the elongatedtube.
 20. The leg positioning apparatus of claim 19, wherein the rod isrotatable within the elongated tube to move at least one of the firstand second clamping device elements to the unclamping position.
 21. Theleg positioning apparatus of claim 14, wherein one of the first andsecond clamping device elements comprises a housing formed to include atapered bore and the other of the first and second clamping deviceelements comprises a pressure block configured to wedge against thetapered bore.
 22. The leg positioning apparatus of claim 21, wherein thehousing includes a recess configured to receive the mounting device andthe pressure block being biased to tighten the recess of the housingagainst the mounting device.
 23. The leg positioning apparatus of claim22, wherein the clamping device includes at least one Belleville washerto bias the pressure block to wedge against the tapered bore.
 24. A legpositioning apparatus comprising a mounting device configured to attachto a surgical table, a support device comprising an elongated memberhaving a longitudinal axis, a leg holder pivotably coupled to thesupport device and adapted to engage and support at least a portion of aleg of a patient, a coupler configured to couple the leg holder to theelongated member, the coupler being configured to permit adjustment of aposition of the leg holder relative to the elongated member about atleast one leg holder axis, a clamping device for mounting a proximateend of the elongated member to the mounting device having a first axistransverse to said longitudinal axis, the clamping device beingconfigured to selectively simultaneously clamp the motion of theelongated member about the first axis and about a second axis transverseto both the first axis and the longitudinal axis and to selectivelysimultaneously release the motion of the elongated member for movementabout said first and second axes, said elongated member being fixed insaid clamping device from rotation about said longitudinal axis, whereinthe clamping device includes a plurality of clamping elements, at leastone first clamping element of the plurality of clamping elements ismovable between a first clamping position to prevent the motion of theelongated member about the first axis and a first releasing position torelease motion of the elongated member about the first axis, at leastone second clamping element of the plurality of clamping elements beingmovable between a second clamping position to prevent the motion of theelongated member about the second axis and a second releasing positionto release motion of the elongated member about the second axis, whereinthe simultaneous motion of the elongated member about the first andsecond axes is permitted after the at least one first clamping deviceelement is moved to the first releasing position and after the at leastone second clamping device element is moved to the second releasingposition, wherein the simultaneous motion of the elongated member aboutthe first and second axes is prevented after the at least one firstclamping device element is moved to the first clamping position andafter the second clamping device element is moved to the second clampingposition, and an operator device comprising a handle coupled to theelongated member and operatively coupled to the clamping device, thecoupler being positioned between the handle and the clamping device, theelongated member extending away from the clamping device beyond thecoupler and the leg holder to a distal end, the handle being situatedbeyond the distal end of the elongated member and movable to move thefirst and second clamping device elements between the respective firstand second clamping positions and the respective first and secondreleasing positions, and the handle being usable to reposition theelongated member about the first and second axes after the first andsecond clamping device elements are moved to the respective first andsecond releasing positions.
 25. The leg positioning apparatus of claim24, wherein the mounting device includes a post that defines the firstaxis.
 26. The leg positioning apparatus of claim 25, wherein at leastone of the first and second clamping device elements clamps against thepost when the first and second clamping device elements are in therespective first and second clamping positions.
 27. The leg positioningapparatus of claim 25, wherein the mounting device includes a blockadapted to be coupled to an accessory rail of a patient-support tableand the post is coupled to the block.
 28. The leg positioning apparatusof claim 25, further comprising a resilient device configured tocounterbalance weight supported by the leg holder, the resilient devicebeing coupled to the mounting device, and the resilient device beingcoupled to the elongated member.
 29. The leg positioning apparatus ofclaim 24, wherein the coupler is configured to be loosened forrepositioning along the elongated member and tightened to preventrepositioning along the elongated member.
 30. The leg positioningapparatus of claim 29, wherein the coupler is rotatable about theelongated member when loosened.
 31. The leg positioning apparatus ofclaim 24, wherein the operator device is rotatable about thelongitudinal axis of the elongated member to move at least one of thefirst and second clamping device elements between the respective firstand second clamping position and the respective first and secondreleasing position.
 32. The leg positioning apparatus of claim 24,further comprising a rod coupled to the operator device and extendingtherefrom toward the clamping device.
 33. The leg positioning apparatusof claim 32, wherein the elongated member comprises a tube having apassage therethrough and at least a portion of the rod is positioned inthe passage.
 34. The leg positioning apparatus of claim 32, wherein aportion of the tube and a portion of the rod extend through the coupler.35. The leg positioning apparatus of claim 24, wherein at least one ofthe first and second clamping device elements is yieldably biasedagainst the mounting device when the first and second clamping deviceelements are in the respective first and second clamping positions. 36.The leg positioning apparatus of claim 24, wherein the mounting devicecomprises a post and at least one of the first and second clampingdevice elements comprises a housing formed to include a recess receivingthe post and a gap extending therefrom such that increasing the size ofthe gap permits rotation of the housing relative to the post.
 37. Theleg positioning apparatus of claim 36, wherein the post defines thefirst axis and the housing is formed to include a bore defining thesecond axis.
 38. The leg positioning apparatus of claim 37, wherein thefirst axis is spaced from the second axis such that the first and secondaxes do not intersect.
 39. The leg positioning apparatus of claim 37,wherein at least one of the first and second clamping device elementscomprises first and second pressure blocks received by the bore, thefirst pressure block being movable relative to the second pressure blockwithin the bore, the first and second pressure blocks engaging thehousing and being configured so that the movement of the first pressureblock toward the second pressure block decreases the length of the gapof the housing and the housing grips the post, thereby blocking rotationof the housing relative to the post.
 40. The leg positioning apparatusof claim 24, wherein at least one of the first and second clampingdevice elements includes a housing and the other of the first and secondclamping device elements comprises a first pressure block received bythe housing, a second pressure block received by the housing, and aspring received by the housing and acting to yieldably bias the firstpressure block toward the second pressure block.
 41. The leg positioningapparatus of claim 40, wherein the first pressure block comprises aproximal end, a distal end, and a head formed on the distal end and thesecond pressure block comprises a proximal end, a distal end, and a headformed on the distal end, and wherein the first and second pressureblocks are movable between an inward position at which the head of thefirst pressure block and the head of the second pressure blockfrictionally engage the housing to block rotation of the first andsecond pressure blocks relative to the housing and an outward positionpermitting rotation of the first and second pressure blocks relative tothe housing.
 42. The leg positioning apparatus of claim 41, wherein atleast one of the first and second pressure blocks is formed to include abore receiving the elongated member so that the elongated member rotatesrelative to the housing when the first and second pressure blocks rotaterelative to the housing and so that movement of the elongated memberrelative to the housing is blocked when the first and second pressureblocks are at the inward position.
 43. The leg positioning apparatus ofclaim 41, wherein the mounting device includes a post, the housing isformed to include a recess receiving the post and a gap extendingtherefrom, the housing being flexible to increase the size of the gap topermit rotation of the housing relative to the post and movement of thefirst and second pressure blocks to the inward position decreases thegap thereby blocking rotation of the housing relative to the post. 44.The leg positioning apparatus of claim 24, wherein the one of the firstand second clamping device elements include a housing and the other ofthe first and second clamping device elements include first and secondpressure blocks that are received by the housing and that are movablerelative to one another between an inward position at which the firstand second clamping device elements are in the respective first andsecond clamping positions and an outward position at which the first andsecond clamping device elements are in the respective releasingpositions.
 45. The leg positioning apparatus of claim 44, furthercomprising an actuator device operatively coupling the operator deviceto at least one of the first and second pressure blocks, the actuatordevice being movable between a first position at which the first andsecond pressure blocks are at the outward position and a second positionat which the first and second pressure blocks are at the inwardposition.
 46. The leg positioning apparatus of claim 45, furthercomprising a rod coupled to the handle and coupled to the actuatordevice so that movement of the handle moves the actuator device.
 47. Theleg positioning apparatus of claim 44, wherein the actuator deviceincludes an eccentric portion, one of the first and second pressureblocks comprises a follower portion, the eccentric portion engaging thefollower portion to move the first and second pressure blocks to theoutward position when the actuator device is rotated in a firstdirection.
 48. A leg positioning apparatus comprising a tube having alongitudinal axis, a mounting device configured to attach to a surgicaltable, a clamping device for mounting a proximate end of the tube to themounting device having a first axis transverse to said longitudinalaxis, the clamping device being configured to selectively simultaneouslyclamp the motion of the tube about the first axis and about a secondaxis transverse to both the first axis and the longitudinal axis and toselectively simultaneously release the motion of the tube for movementabout said first and second axes, said tube being fixed in said clampingdevice from rotation about said longitudinal axis, wherein the clampingdevice includes a plurality of clamping elements, at least one firstclamping element of the plurality of clamping elements is movablebetween a first clamping position to prevent the motion of the tubeabout the first axis and a first releasing position to release motion ofthe tube about the first axis, at least one second clamping element ofthe plurality of clamping elements being movable between a secondclamping position to prevent the motion of the tube about the secondaxis and a second releasing position to release motion of the tube aboutthe second axis, wherein the simultaneous motion of the tube about thefirst and second axes is permitted after the at least one first clampingdevice element is moved to the first releasing position and after the atleast one second clamping device element is moved to the secondreleasing position, wherein the simultaneous motion of the tube aboutthe first and second axes is prevented after the at least one firstclamping device element is moved to the first clamping position andafter the second clamping device element is moved to the second clampingposition, and a leg holder coupled to the tube at a first distance awayfrom the clamping device, and an operator device coupled to the tube ata second distance away from the clamping device, the second distancebeing greater than the first distance, the tube extending away from theclamping device beyond the leg holder to a distal end of the tube, theoperator device being coupled to the tube near the distal end of thetube beyond the leg holder, the operator device being movable to movethe first and second clamping device elements between the respectivefirst and second clamping positions and the respective first and secondreleasing positions.
 49. A leg positioning apparatus comprising amounting device configured to attach to a surgical table, a supportdevice lockable relative to the mounting device and releasable to rotaterelative to the mounting device about a first plurality of axes, thesupport device being tubular and having a longitudinal axis, a clampingdevice for mounting a proximate end of the support device to a mountingdevice having a first axis of the first plurality of axes transverse tosaid longitudinal axis, the clamping device being configured toselectively simultaneously clamp the motion of the support device aboutthe first axis and about a second axis of the first plurality of axestransverse to both the first axis and the longitudinal axis and toselectively simultaneously release the motion of the support device formovement about said first and second axes, said support device beingfixed in said clamping device from rotation about said longitudinalaxis, wherein the clamping device includes a plurality of clampingelements, at least one first clamping element of the plurality ofclamping elements is movable between a first clamping position toprevent the motion of the support device about the first axis and afirst releasing position to release motion of the support device aboutthe first axis, at least one second clamping element of the plurality ofclamping elements being movable between a second clamping position toprevent the motion of the support device about the second axis and asecond releasing position to release motion of the support device aboutthe second axis, wherein the simultaneous motion of the support deviceabout the first and second axes is permitted after the at least onefirst clamping device element is moved to the first releasing positionand after the at least one second clamping device element is moved tothe second releasing position, wherein the simultaneous motion of thesupport device about the first and second axes is prevented after the atleast one first clamping device element is moved to the first clampingposition and after the second clamping device element is moved to thesecond clamping position, a leg holder lockable relative to the supportdevice and releasable to move relative to the support device about asecond plurality of axes, a first handle coupled to the elongated memberand operatively coupled to the clamping device, the support deviceextending away from the clamping device beyond the leg holder to adistal end, the first handle being situated beyond the distal end of thesupport member and movable to move the first and second clamping deviceelements between the respective first and second clamping positions andthe respective first and second releasing positions, and the firsthandle being usable to reposition the elongated member about the firstand second axes after the first and second clamping device elements aremoved to the respective first and second releasing positions, and asecond handle movable to lock the leg holder from moving about thesecond plurality of axes relative to the support device and movable tounlock the leg holder for movement about the second plurality of axesrelative to the support device.
 50. The leg positioning apparatus ofclaim 49, wherein the second handle is positioned between the firsthandle and clamping device.
 51. The leg positioning apparatus of claim49, further comprising a resilient device configured to counterbalanceweight supported by the leg holder, the resilient device being coupledto the mounting device, and the resilient device being coupled to thesupport device.
 52. The leg positioning apparatus of claim 49, whereinthe mounting device includes a block adapted to be coupled to anaccessory rail of a patient-support table.